Aerobic respiration occurs in the mitochondria in the cell. In this process glucose and oxygen produce energy in the form of ATP (adenosine triphosphate) with the
waste products of carbon dioxide and water. The ATP is used to power chemical reactions in the body.
Energy can be produced without oxygen: this is known as anaerobic respiration, but a lot fewer ATP molecules are produced. Purpose:
To observe aerobic respiration in yeast by following the amount of oxygen used.
Material:
Each group will require:
yeast suspension
glucose 20% solution
conical flask
stopper with hole for sensor to pass through or cottonwool or equivalent to seal top of flask
oxygen sensor
thermostatically controlled water bath (optional)
sugar sources such as sucrose, fructose, galactose and sorbose (for Extension activities)
Procedure:
This procedure is given in general terms as data logging equipment varies. Usually classroom activities specify exact amounts. Here only partial details are given. You
will have to use some trial and error over a longer than normal time to decide the 'best' way of doing this experiment.
1.Set up the flask with the yeast and glucose solution. Stand flask in a water bath at 30°C, if available. Insert the oxygen sensor into the flask, making sure the flask is sealed. Allow time for calibration.
2. Record the levels over a suitable time to give the clearest results. This will range from an hour to a couple of days. Trial and error will be involved as well as discussion with your group. You may decide to use a particular temperature in the water bath rather than the classroom temperature, but make sure the rest of the experiment is working before spending time using extra equipment.
Discuss your ideas with your teacher to check on their appropriateness.
Discussion Questions:
Describe the details of what you did. Account for your method.
Draw the oxygen level results in graphical form.
Extension Activities:
Use your equipment to find out what happens to the oxygen level with different temperatures. What happens if sugars other than glucose are used? Try sucrose,
fructose, galactose and sorbose.
References:
Nelson Biology VCE Units 1& 2 Student Activity Manual (2009) Page 78-79.
Introduction:
Aerobic respiration occurs in the mitochondria in the cell. In this process glucose and oxygen produce energy in the form of ATP (adenosine triphosphate) with thewaste products of carbon dioxide and water. The ATP is used to power chemical reactions in the body.
Energy can be produced without oxygen: this is known as anaerobic respiration, but a lot fewer ATP molecules are produced.
Purpose:
To observe aerobic respiration in yeast by following the amount of oxygen used.
Material:
Each group will require:yeast suspension
glucose 20% solution
conical flask
stopper with hole for sensor to pass through or cottonwool or equivalent to seal top of flask
oxygen sensor
thermostatically controlled water bath (optional)
sugar sources such as sucrose, fructose, galactose and sorbose (for Extension activities)
Procedure:
This procedure is given in general terms as data logging equipment varies. Usually classroom activities specify exact amounts. Here only partial details are given. Youwill have to use some trial and error over a longer than normal time to decide the 'best' way of doing this experiment.
1.Set up the flask with the yeast and glucose solution. Stand flask in a water bath at 30°C, if available. Insert the oxygen sensor into the flask, making sure the flask is sealed. Allow time for calibration.
2. Record the levels over a suitable time to give the clearest results. This will range from an hour to a couple of days. Trial and error will be involved as well as discussion with your group. You may decide to use a particular temperature in the water bath rather than the classroom temperature, but make sure the rest of the experiment is working before spending time using extra equipment.
Discuss your ideas with your teacher to check on their appropriateness.
Discussion Questions:
Describe the details of what you did. Account for your method.
Draw the oxygen level results in graphical form.
Extension Activities:
Use your equipment to find out what happens to the oxygen level with different temperatures. What happens if sugars other than glucose are used? Try sucrose,fructose, galactose and sorbose.
References:
Nelson Biology VCE Units 1& 2 Student Activity Manual (2009) Page 78-79.
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